Metallic fastener for envelopes



w E SWIFT METALLIC FASTENER FOR ENVELOPES Filed Oct. 26. 1923 July I 20 1926.

Patented July 20, 1926.

UNITED STATES WILLARD E. SWIFT, OF WORCESTER, MASSACHUSETTS, ASSIGNOR TO UNITED STATES ENVELOPE COMPANY, OF SPRINGFIELD, MASSACHUSETTS, A CORPORATION OF MAINE,

METALLIC FASTENER FOR ENVELOPES- Application filed October 26, 1923, Serial No. 670,964.

My invention relates to an improved metallic fastener for so called merchandise envelopes.

The object of the present invention is to provide a metallic fastener for envelopes, in volving certain advantages and improvements over the type of fastener shown and described in United States Letters Patent of Charles E. Gather, No. 1,290,083, issued January 7, 1919. The fastener of said Gather patent consists of a metal base plate of extended area, attachable by four spurs at its corners to the body ofan envelope. A pair of bendable tongues project laterally, on opposite sides of the base platefrom a narrowed central section thereof. These tongues are adapted to be bent upwardly for insertion together through the closing flap of the envelope, and after the bent-up tongues have been passed through the closing flap'of the envelope, they are bent back lIitO substantially the same plane as the base pate.

It has been found that the bendable tongues of fasteners constructed in accordance with the aforesaid Gather Patent No. 1,290,083, sometimes bend elsewhere than at their bases, and also, even when bending occurs at the bases of said tongues, that a relatively few successive flexures of the bendabletongues causes them to break off, the flexures occuring substantially along straight lines which connect the sharp right angled corners at the junctures between the tongues and the base plate. This last, I have discovered, is because these square cor ners at the bases of the tongues have a tendency to localize the successive flexures or bendings, making them occur almost invariably at the same point at the very base of each tongue.

According to the present invention I provide an improved fastener of the same general type as that shown in the above men'- tioned Gather Patent No. 1,290,083, but'one in which the bendable tongues are so constructed and joined to the base plate that While bending is localized, to the extent of being confined to the vicinity of each tongues base, still the localization to a single point or line is prevented, allowing the tongues to be bent many times more than the tongues of the aforesaid patented fastener, without breaking off. The above and other advantageous features of my invention will hereinafter more fully appear, reference being had to the accompanying'drawings, in

Fig. 3 is a view, showing on an enlarged Y scale, my improved fastener removed from the envelope.

Fig. 4: is a view similar to Fig. 3, showing the manner in which the tongues eventually break as.

Like reference characters refer to like parts in the different figures.

Referring to the drawings, the body of an envelope is indicated at 1, to which is attached a closing flap 2 having an opening -3 therein to receive the tongues of a fastener, generally designated at 4. The fastener 4 is illustrated in a flat, or extended position in Figs, 1 and 3, and comprises a base plate 5 attached to the body 1 of the envelope in any suitable manner, as by spurs 6, 6 at its corners, which pass through the boidy portion and are clinched on theinner s1 e.

Bendable tongues 7 and 8 extend from opposite sides of the plate 5, and as best shown in Fig. 3 the tongues are gradually reduced in width as they approach the plate 5 and they have their edges substantially tangent to curved edge portions 9, 9 of the base plate. The tongue 7 is made longer than the tongue 8, just-as in the fastener shown in the above mentioned Patent No. 1,290,083, in which latter, however, longitudinal edges of the tongues make sharp corners with the edges of the base plate. In the present construction, as in the fastener of the above mentioned Patent No. 1,290,083, the spurs 6 of the base plate lie beyond the outside of the zones of fiexure of the tongues 7 and 8, thereby increasing the resistance of said base plate to the bending force applied to said tongues.

When it is desired to secure the closing flap 2 to the body portion 1 of the envelope, the tongues 7 and 8 are bent upwardly, as

shown in Fig. 2, thereby bringing the ends of the tongues into close proximity, so as to permit their ready insertion into the opening 3 when the closing flap 2 is turned downwardly to close the envelope. As the tongue 7 is longer than the tongue 8, the projecting end of the tongue 7 may then be readily turned down upon the seal flap, leaving the tongue 8 free to be subsequently turned down, thereby securely fastening theclosing flap 2 to the body portion-1. When it is desired to open the envelope it is only necessary to again bend the tongues 7 and 8 into the position shown in Fig. 2, after which the closing flap 2 may be turned back.

By the construction above described, wherein all sharp corners at or near the bases of the bendable tongues 7 and 8 are eliminated, and wherein said tongues are made narrower in their portions at which flexure occurs, the fastener of my invention provides tongues which are sure to bend in the proper location, and one which, under repeated flexures of its tongues, offers greater resistance to fracture. In the actual use of my improved fastener, when the tongues 7 and 8 are bent back and forth several times, it has been found that successive flexures distribute themselves over a zone somewhat removed from the base plate 5, and that there will be a considerable curvature of the tongues where the bending occurs. It has also been found that when either tongue 7 or 8 is bent back and forth several times, the flexures will seldom occur in precisely the same place, but will be distributed throughout the aforesaid zone, of considerable area, between the curved portions 9, as indicated in dotted lines in Fig. 3. As a result, when a tongue is finally broken off by repeated flexure thereof, the fracture occurs along a somewhat irregular line beyond the base plate 5, as illustrated in l -ig. 4. It has been found by actual experiment that the tongues of my improved fastener may be bent many more times than the tongues of a fastener constructed as shown in the above mentioned Patent No. 1,290,088, in which the repeated flexures practically always occur at the same place, namely along a line at the very base of a tongue, and substantially coinciding with the edge of the base plate. Furthermore, the tongues of my nnproved fastener are easily bent by reason of their increased length and reduced section in the zone of bending, while their unreduced end portions provide adequate holdlng surfaces when bentinto the plane of the envelope body.

From the foregoing then, it is apparent that by my invention I have provided an improved metallic fastener for envelopes which is of superior construction and considerably more durable than fasteners of this same type, as previously constructed.

raaaoae I claim,

1. A metallic fastener for envelopes, comprising a base portion provided with means for its attachment to the body of an envelope, and a tongue, integral with said base portion and extending laterally from one side thereof, said tongue being bendable adjacent its juncture with said base portion into and out of the plane thereof, and said tongue making its said juncture edgewise with said base portion by curves which are tangent to its own longitudinal edges, thereby to prevent localization of repeated bendings of said tongue. I

2. A metallic fastener for envelopes, com prising a base portion provided with means for its attachment to the body of an envelope, and a tongue integral with said base portion and extending laterally from one side thereof, with its longitudinal edges converging as the approach juncture with said base portion, said tongue being bendable adjacent its juncture with said base portion into and out of the plane thereof, and said tongues making its said juncture edgewise with said base portion by curves which are tangent to its own longitudinal edges, thereby to prevent localization of repeated bend ings of said tongue.

3. A metallic fastener for envelopes, comprising a base portion, and a tongue integral with said base portion and extending laterally from one side thereof, said tongue being bendable adjacent its juncture with said base portion into and out of the plane thereof, and said base portion having means for its attachment to the body of an envelope at points beyond the zone of bending to said tongue, thereby to increase said base portion s resistance to the bending forces applied to said tongue, the latter making its said juncture edgewise with said base portion by curves which are tangent to its own longitudinal edges, thereby to prevent localization of repeated bendings of said tongue.

at. A metallic fastener for envelopes, comprising a base of substantially rectangular form, with prongs at its four corners for attachment to the body of an envelope, said base providing a portion of reduced width, integral bendable tongues extending laterally from opposite sides of said portion of reduced width, said tongues having their longitudinal edges coverging as they approach juncture with said portion, thereby to confine bending of said tongues to a zone within the area bounded by said attaching prongs of said base, and each of said tongues making its juncture edgewise with said portion of reduced width by curves which are tangent to its longitudinal edges, thereby to prevent localization of repeated bendings in said bending zone.

lVILLARD E. SlVlFT. 

